STUBBORN Misfire ...

[Murray]

You seem to have solved the misfire problem but I'll chime in anyway.

One of the reasons I got rid of my MP3 was an intermittent misfire problem. Since no one could reproduce it consistently, no one would replace anything. I finally traded it in April.

Well I just met its SECOND owner since then (3rd total). He seems to have the misfire fixed and surprise: it was the coil packs, just as I'd suggested to EVERYONE that worked on it. Unfortunately, now he's having other problems due to the person who had it right after me abusing it ... but that's another story.

So I guess the moral is don't discount the possibility of something causing a problem just because it's unlikely. I've heard of several 2001 Proteges having coil pack problems.

And good luck with the idle problem.

 

[lsdeater]

IT IS A RECALL for the 3rd gen coil packs guys!!

 

[lsdeater]

ENJOY!

DTC P0300 (RANDOM MIS-FIRE) - 1.8L COIL PACK
Applicable Models
Model Starting S/N Ending S/N
1999 PROTEGE X0000000 Y0305744
2000 PROTEGE X0000000 Y0305744
1999 PROTEGE X0000000 Y0305744
2000 PROTEGE X0000000 Y0305744

Mil on DTC P0300 stored in memory, customer may or may not
experience a rough idle condition.

Condition may be caused by a failed solder joint between the power
supply terminal and the circuit board within the coil pack due to
thermal stress.

A gel cover was added to the circuit board starting:
August 1, 2000 - begining with VIN No. JM1BJ221*Y0305744

Coil can be identified by Lot No.(ink stamp) on each coil:

EXAMPLE: 081, 0=2000, 8=Aug, 1=Week or the 1st week of Aug. 2000.

 

[Bijou-MP5]

You seem to have solved the misfire problem but I'll chime in anyway.

One of the reasons I got rid of my MP3 was an intermittent misfire problem. Since no one could reproduce it consistently, no one would replace anything. I finally traded it in April.

Well I just met its SECOND owner since then (3rd total). He seems to have the misfire fixed and surprise: it was the coil packs, just as I'd suggested to EVERYONE that worked on it. Unfortunately, now he's having other problems due to the person who had it right after me abusing it ... but that's another story.

So I guess the moral is don't discount the possibility of something causing a problem just because it's unlikely. I've heard of several 2001 Proteges having coil pack problems.

And good luck with the idle problem.

yup, for me misfiring was the due to defective coil pack too, but I still haven't figured it out my low idle problem.
I cleaned EGR valve, it seems like my idle is little better(smooth,doesn't bounce that much but just a little), I'm taking it to dealer next week to get it check.

 

[Diehonda]

IT IS A RECALL for the 3rd gen coil packs guys!!

not mine as it is a P5 2.0, dang it.


Still low idle and too many other things going on. Already replaced the coils and the plugs. I will let you all know.

 

[Bijou-MP5]

not mine as it is a P5 2.0, dang it.


Still low idle and too many other things going on. Already replaced the coils and the plugs. I will let you all know.

seems like you and I have exact same problem.
my car almost stalled again...rpm dropped close to 0 for 2secs and it came back to normal. but don't have check engine light yet..

 

[Diehonda]

strange that your RPM's can drop that much and not throw a CEL. Mine warms up as normal and then once it is fully warmed and I set the idle it drops to a steady 525 but while driving it may catch for a split second and release while accelerating. Not too much but every once in awhile. I will actually have the time to have the CEL ran tomorrow and we will see.

 

[Diehonda]

the famous P0421 - Warm Up Catalyst below threshold (Bank 1). Now to figure out if it is the first cat or the O2 sensor. I just searched on here for awhile, so next step is popping the hood.

 

[Bijou-MP5]

the famous P0421 - Warm Up Catalyst below threshold (Bank 1). Now to figure out if it is the first cat or the O2 sensor. I just searched on here for awhile, so next step is popping the hood.

I had that issue too, check your pipes if you see any leak!!!
mine was having same code and I found out it was my cat pipes was having leak, so I replaced with new gasket and now that problem is gone~

 

[Diehonda]

I had the most difficult time unhooking the PreCat O2 sensor last night. how do you get the plug under it to disconnect from the metal plate without breaking the plug? I can't wait to get this fixed. The idle drops during deceleration now (nuts)

 

[Bijou-MP5]

I had the most difficult time unhooking the PreCat O2 sensor last night. how do you get the plug under it to disconnect from the metal plate without breaking the plug? I can't wait to get this fixed. The idle drops during deceleration now (nuts)

ok I got P0421 code came on too.
but I'm replacing first cat as well as EGR valve tomorrow. if it's bad o2 sensor then I don't know...but I checked my 2nd cat...it was full of ashes inside.
I don't have any rough idle problem s anymore though, but having CEL sucks.
if your mileage is under 80K, put every stock stuff under the hood and take it to dealer. they denied my warranty because I had a K&N intake.

 

[Diehonda]

126k miles, no warantee and tossed the stock air box.

Did you get an OEM cat? How much did it run you?

 

[Bijou-MP5]

126k miles, no warantee and tossed the stock air box.

Did you get an OEM cat? How much did it run you?

first cat I'm getting OEM, but 2nd cat I had to due universal ones. ask local muffler shop for pricing, but local shops don't have OEM ones, because most of time mazda offers 80K emission warranty. anyway, basically 1st cat you have to either get it from dealer or search forum who installed obx header(they remove first cat) and 2nd cat will costs you about $150~$200 depends on your local shop.
dealer asked for both cats to be replaced for $900!!!

 

[Diehonda]

I am going to change to O2, and if that doesn't do it I think I will just spend a bit more and get a header and be done with it. I already have an intake and exhaust so might as well.

 

[Bijou-MP5]

I am going to change to O2, and if that doesn't do it I think I will just spend a bit more and get a header and be done with it. I already have an intake and exhaust so might as well.

if ur car is running fine but getting CEl then it might be o2 sensor.
however, if your idle is rough then...I think it's something else.
I thought about getting header too but obx were out of stock until end of month..
anyway, if you ever need 1st cat, contact Topher, he told me he had 2 of them and one was sold and one was still available.

 

[ebmp5]

the famous P0421 - Warm Up Catalyst below threshold (Bank 1). Now to figure out if it is the first cat or the O2 sensor. I just searched on here for awhile, so next step is popping the hood.

u may need to do a mil fix if u are getting a po421

 

[Diehonda]

But I don't want a quick fix. If I get a new header I will do it because then I will know the condition of the parts I am running a bypass for. But if the cat is bad and I run the MIL then it could have a melt down and trash my whole system, let alone my mpg. But yes, that idea is in the works.

 

[MatP5]

same problem!

I have the same miss fire problem!

Protege5 2002 with 96 000 km

At first it was the low rpm's, as if the car wanted to stall, I cleaned the EGR valve and no more low rpm.

Now I'm getting miss fires, changed the plugs, back to stock wires, but still miss fires.

It's probably the coil packs????

 

[Diehonda]

Yep, sounds like the coils. Any CEL? What cylinders are misfiring. Switch your coils and see if the misfires moves with it. If so then replace that coil. Rockauto has them for cheap. Just takes four days to receive them due to a two day delay.

So cleaning your EGR fixed you low idle? The valve or the pipe?

 

[MatP5]

miss fire!

Yes! Everytime, the engine light flashes a couple times, then it stays on a day or two.

Switching the coils is a good idea, I'll try that!

Yes, cleaning the egr fix my low iddle. Valve or pipe? The valve I guess, I followed the how-to on this site. Cleaned it with break cleaner then I put a few drops of oil on the spring. I noticed that before cleaning and oiling the spring, the valve would be hard to open and close. After, the valve was alot smoother.

How much do the coils costs?

Thanks